A few days ago I’ve posted an article called “Hey Drummonds forget SSD – RAM is the future” on my website. In this article I’m showing a proof of concept with a recorded demo with some performance measurement on an VMFS with live virtual machines in RAM. It attracted a lot of comments. Of course I know when you lose power you also will lose your VMFS, but maybe that’s not a real problem. It’s depending on what type of virtual machines you are hosting and there’re other techniques like FT to create a higher level of availability to protect the virtual machines from host failures.
One of the people who commented on the article is Steve Jin, he’s running a great weblog called DoubleCloud. Steve has pointed me to a research project from Stanford University called RAMCloud. VMware founder Mendel is involved in this project. The paper “The Case for RAMClouds: Scalable High-Performance Storage Entirely in DRAM” can be downloaded from this location.
Disk-oriented approaches to online storage are becoming increasingly problematic: they do not scale grace-fully to meet the needs of large-scale Web applications, and improvements in disk capacity have far out-stripped improvements in access latency and bandwidth. This paper argues for a new approach to datacenter storage called RAMCloud, where information is kept entirely in DRAM and large-scale systems are created by aggregating the main memories of thousands of commodity servers. We believe that RAMClouds can provide durable and available storage with 100-1000x the throughput of disk-based systems and 100-1000x lower access latency. The combination of low latency and large scale will enable a new breed of data-intensive applications.
